mmc: block: add handling for two parallel block requests in issue_rw_rq
Change mmc_blk_issue_rw_rq() to become asynchronous.
The execution flow looks like this:
* The mmc-queue calls issue_rw_rq(), which sends the request
to the host and returns back to the mmc-queue.
* The mmc-queue calls issue_rw_rq() again with a new request.
* This new request is prepared in issue_rw_rq(), then it waits for
the active request to complete before pushing it to the host.
* When the mmc-queue is empty it will call issue_rw_rq() with a NULL
req to finish off the active request without starting a new request.
Signed-off-by: Per Forlin <per.forlin@linaro.org>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Venkatraman S <svenkatr@ti.com>
Tested-by: Sourav Poddar <sourav.poddar@ti.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 7ed2c68..38d0149 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -822,12 +822,14 @@
R1_CC_ERROR | /* Card controller error */ \
R1_ERROR) /* General/unknown error */
-int mmc_blk_err_check(struct mmc_blk_request *brq,
- struct request *req,
- struct mmc_card *card,
- struct mmc_blk_data *md)
+static int mmc_blk_err_check(struct mmc_card *card,
+ struct mmc_async_req *areq)
{
- int ret = MMC_BLK_SUCCESS;
+ enum mmc_blk_status ret = MMC_BLK_SUCCESS;
+ struct mmc_queue_req *mq_mrq = container_of(areq, struct mmc_queue_req,
+ mmc_active);
+ struct mmc_blk_request *brq = &mq_mrq->brq;
+ struct request *req = mq_mrq->req;
/*
* sbc.error indicates a problem with the set block count
@@ -1038,24 +1040,41 @@
brq->data.sg_len = i;
}
+ mqrq->mmc_active.mrq = &brq->mrq;
+ mqrq->mmc_active.err_check = mmc_blk_err_check;
+
mmc_queue_bounce_pre(mqrq);
}
-static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
+static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
{
struct mmc_blk_data *md = mq->data;
struct mmc_card *card = md->queue.card;
struct mmc_blk_request *brq = &mq->mqrq_cur->brq;
int ret = 1, disable_multi = 0, retry = 0;
enum mmc_blk_status status;
+ struct mmc_queue_req *mq_rq;
+ struct request *req;
+ struct mmc_async_req *areq;
+
+ if (!rqc && !mq->mqrq_prev->req)
+ return 0;
do {
- mmc_blk_rw_rq_prep(mq->mqrq_cur, card, disable_multi, mq);
- mmc_wait_for_req(card->host, &brq->mrq);
+ if (rqc) {
+ mmc_blk_rw_rq_prep(mq->mqrq_cur, card, 0, mq);
+ areq = &mq->mqrq_cur->mmc_active;
+ } else
+ areq = NULL;
+ areq = mmc_start_req(card->host, areq, (int *) &status);
+ if (!areq)
+ return 0;
- mmc_queue_bounce_post(mq->mqrq_cur);
+ mq_rq = container_of(areq, struct mmc_queue_req, mmc_active);
+ brq = &mq_rq->brq;
+ req = mq_rq->req;
+ mmc_queue_bounce_post(mq_rq);
- status = mmc_blk_err_check(brq, req, card, md);
switch (status) {
case MMC_BLK_SUCCESS:
case MMC_BLK_PARTIAL:
@@ -1066,6 +1085,19 @@
ret = __blk_end_request(req, 0,
brq->data.bytes_xfered);
spin_unlock_irq(&md->lock);
+ if (status == MMC_BLK_SUCCESS && ret) {
+ /*
+ * The blk_end_request has returned non zero
+ * even though all data is transfered and no
+ * erros returned by host.
+ * If this happen it's a bug.
+ */
+ printk(KERN_ERR "%s BUG rq_tot %d d_xfer %d\n",
+ __func__, blk_rq_bytes(req),
+ brq->data.bytes_xfered);
+ rqc = NULL;
+ goto cmd_abort;
+ }
break;
case MMC_BLK_CMD_ERR:
goto cmd_err;
@@ -1087,9 +1119,19 @@
ret = __blk_end_request(req, -EIO,
brq->data.blksz);
spin_unlock_irq(&md->lock);
+ if (!ret)
+ goto start_new_req;
break;
}
+ if (ret) {
+ /*
+ * In case of a none complete request
+ * prepare it again and resend.
+ */
+ mmc_blk_rw_rq_prep(mq_rq, card, disable_multi, mq);
+ mmc_start_req(card->host, &mq_rq->mmc_active, NULL);
+ }
} while (ret);
return 1;
@@ -1124,6 +1166,12 @@
ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req));
spin_unlock_irq(&md->lock);
+ start_new_req:
+ if (rqc) {
+ mmc_blk_rw_rq_prep(mq->mqrq_cur, card, 0, mq);
+ mmc_start_req(card->host, &mq->mqrq_cur->mmc_active, NULL);
+ }
+
return 0;
}
@@ -1133,26 +1181,34 @@
struct mmc_blk_data *md = mq->data;
struct mmc_card *card = md->queue.card;
- mmc_claim_host(card->host);
+ if (req && !mq->mqrq_prev->req)
+ /* claim host only for the first request */
+ mmc_claim_host(card->host);
+
ret = mmc_blk_part_switch(card, md);
if (ret) {
ret = 0;
goto out;
}
- if (req->cmd_flags & REQ_DISCARD) {
+ if (req && req->cmd_flags & REQ_DISCARD) {
+ /* complete ongoing async transfer before issuing discard */
+ if (card->host->areq)
+ mmc_blk_issue_rw_rq(mq, NULL);
if (req->cmd_flags & REQ_SECURE)
ret = mmc_blk_issue_secdiscard_rq(mq, req);
else
ret = mmc_blk_issue_discard_rq(mq, req);
- } else if (req->cmd_flags & REQ_FLUSH) {
+ } else if (req && req->cmd_flags & REQ_FLUSH) {
ret = mmc_blk_issue_flush(mq, req);
} else {
ret = mmc_blk_issue_rw_rq(mq, req);
}
out:
- mmc_release_host(card->host);
+ if (!req)
+ /* release host only when there are no more requests */
+ mmc_release_host(card->host);
return ret;
}
